STEP 1: Extracted Data

{'project_info': {'boring_number': 'B-1, B-2, B-3', 'location': 'Santa Rosa Beach, Walton County, Florida', 'date': 'April 1, 2020', 'ground_surface_elevation': None}, 'groundwater_depth': 10.0, 'soil_layers': [{'depth_from': 0.0, 'depth_to': 5.0, 'elevation_from': 100.0, 'elevation_to': 95.0, 'soil_type': 'Silty Fine-Grained Sand', 'description': 'Very loose dark grey silty fine-grained SAND with many organics - organic silt (SM)', 'unit_weight': 110.0, 'spt_n_field': 8, 'sigma_v': 550.0, 'sigma_v_prime': 550.0, 'n60': 8.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 2000.0, 'moisture_content': None}, {'depth_from': 5.0, 'depth_to': 10.0, 'elevation_from': 95.0, 'elevation_to': 90.0, 'soil_type': 'Silty Fine-Grained Sand', 'description': 'Loose light grey slightly silty fine-grained SAND (SP-SM)', 'unit_weight': 110.0, 'spt_n_field': 11, 'sigma_v': 660.0, 'sigma_v_prime': 660.0, 'n60': 11.0, 'cn': None, 'n1_60': None, 'phi_prime': None, 'cohesion': 2750.0, 'moisture_content': None}, {'depth_from': 10.0, 'depth_to': 15.0, 'elevation_from': 90.0, 'elevation_to': 85.0, 'soil_type': 'Silty Fine-Grained Sand', 'description': 'Medium dense to dense grey/brown to grey fine-grained SAND (SP)', 'unit_weight': 125.0, 'spt_n_field': 15, 'sigma_v': 875.0, 'sigma_v_prime': 875.0, 'n60': 15.0, 'cn': 1.5, 'n1_60': 22.5, 'phi_prime': 34.5, 'cohesion': None, 'moisture_content': None}, {'depth_from': 15.0, 'depth_to': 25.0, 'elevation_from': 85.0, 'elevation_to': 75.0, 'soil_type': 'Fine-Grained Sand', 'description': 'Dense dark grey slightly silty fine-grained SAND with some organics - organic silt (SP-SM)', 'unit_weight': 125.0, 'spt_n_field': 19, 'sigma_v': 1140.0, 'sigma_v_prime': 1140.0, 'n60': 19.0, 'cn': 1.7, 'n1_60': 32.3, 'phi_prime': 36.0, 'cohesion': None, 'moisture_content': None}], 'design_summary': [{'layer_description': 'Silty Fine-Grained Sand (0-5 ft)', 'parameter_type': 'cohesion', 'recommended_value': 2000.0, 'unit': 'psf', 'range': '1800-2200 psf'}, {'layer_description': 'Fine-Grained Sand (10-25 ft)', 'parameter_type': 'phi_prime', 'recommended_value': 34.5, 'unit': 'degrees', 'range': '30-36 degrees'}], 'plot_data': {'depths': [0, 2.5, 5, 10, 15, 20], 'phi_prime_values': [None, None, None, 34.5, 36.0, None], 'cohesion_values': [2000, None, None, None, None, None]}, 'notes': 'Groundwater was encountered at depths varying between approximately 0.5 ft to 3.75 ft BEG.', 'designs': [{'timestamp': '2026-08-06T21:01:17.837457+00:00', 'design_load': 20.0, 'safety_factor': 2.0, 'shaft_system': None, 'use_ai': True, 'result': {'design_load': 20.0, 'safety_factor': 2.0, 'required_ultimate_capacity': 40.0, 'ai_recommendations': {'recommended_min_depth': 5.83, 'recommended_max_depth': 25.5, 'recommended_shaft_systems': ['SS150', 'SS175'], 'depth_rationale': 'The minimum depth is determined by the 14-inch helix requirement of 5.83 ft. The maximum depth is based on engaging the dense sand layer at 25.5 ft.', 'shaft_rationale': 'SS150 and SS175 are selected based on their ability to meet the 40 kip ultimate capacity requirement and their torque capacity.', 'bearing_layer_analysis': 'Key bearing layers are Layer 3 and Layer 4, which are dense sands with a friction angle of 30° and a unit weight of 125 pcf.', 'design_alternatives': [{'name': 'Option 1: SS175 Triple Helix 10"-12"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 10, 'depth': 15.0, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 12, 'depth': 18.5, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 14, 'depth': 22.0, 'soil_layer': 'Dense Sand'}], 'estimated_depth': 22.0, 'minimum_torque': 10000, 'torque_correlation_factor': 10, 'priority': 1, 'rationale': 'Engages the dense sand layer for maximum bearing capacity. The design is controlled by the SS175 mechanical limit.', 'advantages': ['High load capacity', 'Engages strong soil layers', 'Adequate torque capacity'], 'considerations': ['Requires high installation torque', 'Deeper installation'], 'failure_analysis': 'Would fail if installation torque cannot reach 10,000 ft-lb or if dense sand layer is not encountered at expected depth', 'installation_specs': {'min_torque_ftlb': 10000, 'embedment_depth_ft': 22.0, 'termination_criteria': 'Achieve both 22 ft depth AND 10,000 ft-lb torque', 'buckling_check': 'N > 10 in bearing strata - adequate'}}, {'name': 'Option 2: SS150 Double Helix 12"-14"', 'shaft_system': 'SS150', 'helix_configuration': [{'diameter': 12, 'depth': 20.0, 'soil_layer': 'Medium Sand'}, {'diameter': 14, 'depth': 23.5, 'soil_layer': 'Dense Sand'}], 'estimated_depth': 23.5, 'minimum_torque': 7000, 'torque_correlation_factor': 10, 'priority': 2, 'rationale': 'Economical option for moderate loads, engaging the dense sand layer.', 'advantages': ['Lower cost', 'Moderate installation depth', 'Lower torque requirement'], 'considerations': ['May be capacity-limited', 'Less redundancy than triple helix'], 'failure_analysis': 'Would fail if soil conditions are weaker than anticipated or if only one helix engages bearing layer', 'installation_specs': {'min_torque_ftlb': 7000, 'embedment_depth_ft': 23.5, 'termination_criteria': 'Achieve both 23.5 ft depth AND 7,000 ft-lb torque', 'buckling_check': 'N > 15 in bearing strata - adequate'}}], 'soil_analysis': 'The soil stratigraphy consists of four layers with varying properties. The key bearing layers are the dense sand layers (Layer 3 and Layer 4) with a friction angle of 30° and a unit weight of 125 pcf, providing high bearing capacity.', 'recommendations_summary': 'The recommended designs engage the dense sand layers for optimal bearing capacity. The SS175 system with a triple helix configuration provides the highest capacity, while the SS150 with a double helix offers a more economical solution for moderate loads. Both designs meet the A.B. Chance methodology requirements.'}, 'design_parameters': {'min_depth': 5.83, 'max_depth': 25.5, 'shaft_system': 'SS150'}, 'calculated_designs': [{'name': 'Option 1: SS175 Triple Helix 10"-12"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 10, 'depth': 15.0, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 12, 'depth': 18.5, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 14, 'depth': 22.0, 'soil_layer': 'Dense Sand'}], 'ultimate_capacity': 79.65993749999998, 'allowable_capacity': 39.82996874999999, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 1.9914984374999996, 'priority': 1, 'rationale': 'Engages the dense sand layer for maximum bearing capacity. The design is controlled by the SS175 mechanical limit.', 'advantages': ['High load capacity', 'Engages strong soil layers', 'Adequate torque capacity'], 'considerations': ['Requires high installation torque', 'Deeper installation'], 'capacity_details': {'shaft_system': 'SS175', 'num_helices': 3, 'helix_details': [{'helix_diameter': 10, 'depth': 15.0, 'helix_area': 0.531, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 1.725, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 25.875, 'cohesion_component': 0.0, 'friction_component': 25.875, 'capacity_soil': 13.739625, 'capacity_mechanical': 100, 'capacity_ultimate': 13.739625, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 10" helix', 'calculation': 'Ah = 0.531 sq.ft', 'result': 0.531, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 15.0 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 1.725 ksf (at depth 15.0 ft)', 'result': 1.725, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 1.725×15.00\nqult = 0.00 + 25.88\nqult = 25.88 ksf', 'result': 25.875, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.531 × 25.88\nQh = 13.74 kips', 'result': 13.739625, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(13.74, 100.00)\nQult = 13.74 kips\nControlled by: Soil', 'result': 13.739625, 'units': 'kips'}]}, {'helix_diameter': 12, 'depth': 18.5, 'helix_area': 0.771, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.1625, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 32.4375, 'cohesion_component': 0.0, 'friction_component': 32.4375, 'capacity_soil': 25.0093125, 'capacity_mechanical': 100, 'capacity_ultimate': 25.0093125, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 18.5 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.163 ksf (at depth 18.5 ft)', 'result': 2.1625, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.163×15.00\nqult = 0.00 + 32.44\nqult = 32.44 ksf', 'result': 32.4375, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 32.44\nQh = 25.01 kips', 'result': 25.0093125, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(25.01, 100.00)\nQult = 25.01 kips\nControlled by: Soil', 'result': 25.0093125, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 22.0, 'helix_area': 1.049, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.6, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 39.0, 'cohesion_component': 0.0, 'friction_component': 39.0, 'capacity_soil': 40.910999999999994, 'capacity_mechanical': 80.0, 'capacity_ultimate': 40.910999999999994, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 22.0 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.600 ksf (at depth 22.0 ft)', 'result': 2.6, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.600×15.00\nqult = 0.00 + 39.00\nqult = 39.00 ksf', 'result': 39.0, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 39.00\nQh = 40.91 kips', 'result': 40.910999999999994, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(40.91, 80.00)\nQult = 40.91 kips\nControlled by: Soil', 'result': 40.910999999999994, 'units': 'kips'}]}], 'total_ultimate_capacity': 79.65993749999998, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 7965, 'max_torque_rating_ftlb': 10000, 'torque_adequate': True, 'embedment_depth_ft': 22.0, 'termination_criteria': 'Achieve both 22.0 ft depth AND 7,965 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}, {'name': 'Option 2: SS150 Double Helix 12"-14"', 'shaft_system': 'SS150', 'helix_configuration': [{'diameter': 12, 'depth': 20.0, 'soil_layer': 'Medium Sand'}, {'diameter': 14, 'depth': 23.5, 'soil_layer': 'Dense Sand'}], 'ultimate_capacity': 71.0390625, 'allowable_capacity': 35.51953125, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 1.7759765625, 'priority': 2, 'rationale': 'Economical option for moderate loads, engaging the dense sand layer.', 'advantages': ['Lower cost', 'Moderate installation depth', 'Lower torque requirement'], 'considerations': ['May be capacity-limited', 'Less redundancy than triple helix'], 'capacity_details': {'shaft_system': 'SS150', 'num_helices': 2, 'helix_details': [{'helix_diameter': 12, 'depth': 20.0, 'helix_area': 0.771, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.35, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 35.25, 'cohesion_component': 0.0, 'friction_component': 35.25, 'capacity_soil': 27.17775, 'capacity_mechanical': 70, 'capacity_ultimate': 27.17775, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 20.0 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.350 ksf (at depth 20.0 ft)', 'result': 2.35, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.350×15.00\nqult = 0.00 + 35.25\nqult = 35.25 ksf', 'result': 35.25, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 35.25\nQh = 27.18 kips', 'result': 27.17775, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS150 ultimate capacity', 'calculation': 'Qs = 70.00 kips', 'result': 70, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(27.18, 70.00)\nQult = 27.18 kips\nControlled by: Soil', 'result': 27.17775, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 23.5, 'helix_area': 1.049, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.7875, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 41.8125, 'cohesion_component': 0.0, 'friction_component': 41.8125, 'capacity_soil': 43.8613125, 'capacity_mechanical': 56.0, 'capacity_ultimate': 43.8613125, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 23.5 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.788 ksf (at depth 23.5 ft)', 'result': 2.7875, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.788×15.00\nqult = 0.00 + 41.81\nqult = 41.81 ksf', 'result': 41.8125, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 41.81\nQh = 43.86 kips', 'result': 43.8613125, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS150 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 70.0 × 0.8\nQs = 56.00 kips', 'result': 56.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(43.86, 56.00)\nQult = 43.86 kips\nControlled by: Soil', 'result': 43.8613125, 'units': 'kips'}]}], 'total_ultimate_capacity': 71.0390625, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 7103, 'max_torque_rating_ftlb': 7000, 'torque_adequate': False, 'embedment_depth_ft': 23.5, 'termination_criteria': 'Achieve both 23.5 ft depth AND 7,103 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}], 'best_design': {'name': 'Option 1: SS175 Triple Helix 10"-12"-14"', 'shaft_system': 'SS175', 'helix_configuration': [{'diameter': 10, 'depth': 15.0, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 12, 'depth': 18.5, 'soil_layer': 'Fine-Grained Sand'}, {'diameter': 14, 'depth': 22.0, 'soil_layer': 'Dense Sand'}], 'ultimate_capacity': 79.65993749999998, 'allowable_capacity': 39.82996874999999, 'design_load': 20.0, 'safety_factor': 2.0, 'passes': True, 'capacity_ratio': 1.9914984374999996, 'priority': 1, 'rationale': 'Engages the dense sand layer for maximum bearing capacity. The design is controlled by the SS175 mechanical limit.', 'advantages': ['High load capacity', 'Engages strong soil layers', 'Adequate torque capacity'], 'considerations': ['Requires high installation torque', 'Deeper installation'], 'capacity_details': {'shaft_system': 'SS175', 'num_helices': 3, 'helix_details': [{'helix_diameter': 10, 'depth': 15.0, 'helix_area': 0.531, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 1.725, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 25.875, 'cohesion_component': 0.0, 'friction_component': 25.875, 'capacity_soil': 13.739625, 'capacity_mechanical': 100, 'capacity_ultimate': 13.739625, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 10" helix', 'calculation': 'Ah = 0.531 sq.ft', 'result': 0.531, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 15.0 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 1.725 ksf (at depth 15.0 ft)', 'result': 1.725, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 1.725×15.00\nqult = 0.00 + 25.88\nqult = 25.88 ksf', 'result': 25.875, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.531 × 25.88\nQh = 13.74 kips', 'result': 13.739625, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(13.74, 100.00)\nQult = 13.74 kips\nControlled by: Soil', 'result': 13.739625, 'units': 'kips'}]}, {'helix_diameter': 12, 'depth': 18.5, 'helix_area': 0.771, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.1625, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 32.4375, 'cohesion_component': 0.0, 'friction_component': 32.4375, 'capacity_soil': 25.0093125, 'capacity_mechanical': 100, 'capacity_ultimate': 25.0093125, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 12" helix', 'calculation': 'Ah = 0.771 sq.ft', 'result': 0.771, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 18.5 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.163 ksf (at depth 18.5 ft)', 'result': 2.1625, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.163×15.00\nqult = 0.00 + 32.44\nqult = 32.44 ksf', 'result': 32.4375, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 0.771 × 32.44\nQh = 25.01 kips', 'result': 25.0093125, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity', 'calculation': 'Qs = 100.00 kips', 'result': 100, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(25.01, 100.00)\nQult = 25.01 kips\nControlled by: Soil', 'result': 25.0093125, 'units': 'kips'}]}, {'helix_diameter': 14, 'depth': 22.0, 'helix_area': 1.049, 'soil_type': 'Fine-Grained Sand', 'spt_n_value': 10, 'cohesion': 0.0, 'friction_angle': 30.0, 'overburden_pressure': 2.6, 'bearing_factor_nq': 15.0, 'bearing_capacity_per_unit_area': 39.0, 'cohesion_component': 0.0, 'friction_component': 39.0, 'capacity_soil': 40.910999999999994, 'capacity_mechanical': 80.0, 'capacity_ultimate': 40.910999999999994, 'controlling_factor': 'Soil', 'calculation_steps': [{'step': 1, 'description': 'Helix Area Lookup', 'formula': 'Ah = Area of 14" helix', 'calculation': 'Ah = 1.049 sq.ft', 'result': 1.049, 'units': 'sq.ft'}, {'step': 2, 'description': 'Soil Properties at Helix Depth', 'formula': 'At depth = 22.0 ft', 'calculation': 'Soil Type: Fine-Grained Sand\nSPT N-value: 10\nCohesion (c): 0.00 ksf\nFriction Angle (φ): 30.0°', 'result': {'cohesion': 0.0, 'friction_angle': 30.0}, 'units': 'various'}, {'step': 3, 'description': 'Effective Overburden Pressure', 'formula': 'q = Σ(γ × thickness) for each layer', 'calculation': 'q = 2.600 ksf (at depth 22.0 ft)', 'result': 2.6, 'units': 'ksf'}, {'step': 4, 'description': 'Bearing Capacity Factor (Nq)', 'formula': 'Nq = f(φ = 30.0°)', 'calculation': 'Nq = 15.00 (interpolated from bearing capacity tables)', 'result': 15.0, 'units': 'dimensionless'}, {'step': 5, 'description': 'Bearing Capacity per Unit Area', 'formula': 'qult = Nc×c + q×Nq (where Nc = 9.0 for deep foundations)', 'calculation': 'qult = 9.0×0.00 + 2.600×15.00\nqult = 0.00 + 39.00\nqult = 39.00 ksf', 'result': 39.0, 'units': 'ksf'}, {'step': 6, 'description': 'Total Soil Bearing Capacity', 'formula': 'Qh = Ah × qult', 'calculation': 'Qh = 1.049 × 39.00\nQh = 40.91 kips', 'result': 40.910999999999994, 'units': 'kips'}, {'step': 7, 'description': 'Mechanical Capacity Limit', 'formula': 'Qs = SS175 ultimate capacity × 0.8 (14" helix reduction)', 'calculation': 'Qs = 100.0 × 0.8\nQs = 80.00 kips', 'result': 80.0, 'units': 'kips'}, {'step': 8, 'description': 'Ultimate Capacity (Controlling)', 'formula': 'Qult = min(Qh, Qs)', 'calculation': 'Qult = min(40.91, 80.00)\nQult = 40.91 kips\nControlled by: Soil', 'result': 40.910999999999994, 'units': 'kips'}]}], 'total_ultimate_capacity': 79.65993749999998, 'calculation_method': 'Chance Individual Bearing Method'}, 'installation_specifications': {'torque_correlation_factor': 10, 'min_installation_torque_ftlb': 7965, 'max_torque_rating_ftlb': 10000, 'torque_adequate': True, 'embedment_depth_ft': 22.0, 'termination_criteria': 'Achieve both 22.0 ft depth AND 7,965 ft-lb torque', 'buckling_check': {'min_n_value': 10, 'adequate': True, 'note': 'Adequate (N > 4)'}}}, 'num_passing_designs': 2}}]}